In: Statistics and Probability
1. An animal behavior group wanted to determine what proportion of puppies (less than 1-year-old) barked at themselves in a mirror. Out of 55 puppies surveyed, 32 barked at themselves when they were put in front of a mirror. What is the 99% confidence interval of the true proportion of puppies who do this?
2. A soccer coach believes that 78% of young soccer players have one or both parents who also played soccer. How large of a sample would she need to estimate the true proportion of young soccer players with ‘soccer’ parents within 4% with 90% confidence?
3. A sample of 35 world cities showed an average daily temperature in July of 78. 9 ̊F. Assume the population standard deviation is 8.7 ̊F. What is the best point estimate for the average temperature? Make a 95% confidence interval for the true average daily temperature in July for world cities.